Conditionals

Posted by Tae Kim

How to say "if" in Japanese

This whole section is dedicated to learning how to say "if" in Japanese. Oh, if only it was as simple as English. In Japanese, there's four (count them, four) ways to say "if"! Thankfully, the conjugations are sparse and easy especially since you don't have to deal with tenses.

Expressing natural consequence using 「と」

Vocabulary

ボール - ball

落とす 【お・とす】 (u-verb) - to drop

落ちる 【お・ちる】 (ru-verb) - to fall

電気 【でん・き】 - electricity; (electric) light

消す 【け・す】 (u-verb) - to erase

暗い 【くら・い】 (i-adj) - dark

学校 【がっ・こう】 - school

行く 【い・く】 (u-verb) - to go

友達 【とも・だち】 - friend

会う 【あ・う】 (u-verb) - to meet

たくさん - a lot (amount)

太る 【ふと・る】 (u-verb) - to become fatter

先生 【せん・せい】 - teacher

きっと - for sure

年上 【とし・うえ】 - older

We'll first cover the simplest type of "if" which is the natural consequence conditional. This means that if [X] happens, [Y] will happen as a natural consequence. No question about it. If I drop a ball, it will fall to the ground. If I turn off the lights at night, it will get dark. We can express this type of condition in the following format.

Rules for using the conditional 「と」

Attach 「と」 to the condition followed by the result that would occur should the condition be satisfied= [Condition] + と + [Result]

State-of-being must be made explicit= [State-of-being] + だと + [Result]

Examples

ボールを落すと落ちる。
If you drop the ball, it will fall.

電気を消すと暗くなる。
If you turn off the lights, it will get dark.

These examples are designed to show how 「と」 is used to express natural consequence. However, even if the statement isn't a natural consequence in itself, the 「と」 will tell the audience that it is nevertheless expected to be a natural consequence.

学校に行かないと友達と会えないよ。
If you don't go to school, you can't meet your friends.

たくさん食べると太るよ。
If you eat a lot, you will get fat, for sure.

先生だと、きっと年上なんじゃないですか？
If he's a teacher, he must be older for sure, right?

The "for sure" part is the implied meaning supplied by the 「と」. The speaker is saying that the following condition will occur in that situation, no matter what. As you can see from the last example, if the condition is a state-of-being, it must be expressed so explicitly using 「だ」. This applies to all non-conjugated nouns and na-adjectives as I'm sure you're used to by now. This will also help prevent confusion with other types of 「と」.

Contextual conditionals using 「なら（ば）」

Vocabulary

皆 【みんな】 - everybody

行く 【い・く】 (u-verb) - to go

私 【わたし】 - me, myself, I

言う 【い・う】 (u-verb) - to say

問題 【もん・だい】 - problem

ある (u-verb) - to exist (inanimate)

図書館 【と・しょ・かん】 - library

あそこ - over there

Another relatively easy to understand type of "if" is the contextual conditional. You can use this particle to express what will happen given a certain context. For example, if you wanted to say, "Well, if everybody's going, I'm going too" you would use the 「なら」 conditional because you are saying that you will go in the context of everybody else going. The contextual conditional always requires a context in which the conditional occurs. For instance, you would use it for saying things like, "If that's what you are talking about..." or "If that's the case, then..."

In a sense, you are explaining what would occur if you assume a certain condition is satisfied. In other words, you are saying "if given a certain context, here is what will happen." You will see this reflected in the English translations as the phrase "if given" in the examples.

The 「なら」 is attached to the context in which the conditional occurs. The format is the same as the 「と」 conditional, however, you must not attach the declarative 「だ」.

Rules for using the contextual conditional 「なら」

Attach 「なら」 to the context in which the conditional would occur= [Assumed Context] + なら + [Result]

You must not attach the declarative 「だ」.

Examples

みんなが行くなら私も行く。
If given that everybody is going, then I'll go too.

アリスさんが言うなら問題ないよ。
If given that Alice-san says so, there's no problem.

Example Dialogue

アリス：図書館はどこですか。
Alice: Where is the library?

ボブ：図書館なら、あそこです。
Bob: If given that you're talking about the library, then it's over there.

The following is incorrect.

図書館だならあそこです。

You can also decide to use 「ならば」 instead of just 「なら」. This means exactly the same thing except that it has a more formal nuance.

General conditionals using 「ば」

Vocabulary

食べる 【た・べる】 (ru-verb) - to eat

待つ 【ま・つ】 (u-verb) - to wait

おかしい (i-adj) - funny

ある (u-verb) - to exist (inanimate)

学生 【がく・せい】 - student

暇 【ひま】 - free (as in not busy)

友達 【とも・だち】 - friend

会う 【あ・う】 (u-verb) - to meet

買い物 【か・い・もの】 - shopping

行く 【い・く】 (u-verb) - to go

お金 【お・かね】 - money

いい (i-adj) - good

楽しい 【たの・しい】 (i-adj) - fun

私 【わたし】 - me; myself; I

病気 【びょう・き】 - disease; sickness

なる (u-verb) - to become

The next type of conditional just expresses a regular "if" condition without any assumptions or embedded meanings. The conjugation rules for the 「ば」 conditional is below. Note, the conjugation rule for nouns and na-adjectives is actually using the verb 「ある」 in 「である」, a formal expression we'll learn much later.

Conjugation Rules for 「ば」

For verbs: Change the last /u/ vowel sound to the equivalent /e/ vowel sound and attach 「ば」
Examples

食べる → 食べれ → 食べれば

待つ → 待て → 待てば

For i-adjectives or negatives ending in 「ない」: Drop the last 「い」 and attach 「ければ」.
Examples

おかしい → おかしければ

ない → なければ

For nouns and na-adjectives: Attach 「であれば」
Examples

学生 → 学生であれば

暇 → 暇であれば

Examples

友達に会えれば、買い物に行きます。
If I can meet with my friend, we will go shopping.

お金があればいいね。
If I had money, it would be good, huh?

楽しければ、私も行く。
If it's fun, I'll go too.

楽しくなければ、私も行かない。
If it's not fun, I'll also not go.

食べなければ病気になるよ。
If you don't eat, you will become sick.

Past conditional using 「たら（ば）」

Vocabulary

自動 【じ・どう】 - automatic

待つ 【ま・つ】 (u-verb) - to wait

読む 【よ・む】 (u-verb) - to read

忙しい 【いそが・しい】 (i-adj) - busy

暇 【ひま】 - free (as in not busy)

遊ぶ 【あそ・ぶ】 (u-verb) - to play

行く 【い・く】 (u-verb) - to go

学生 【がく・せい】 - student

割引 【わり・びき】 - discount

買う 【か・う】 (u-verb) - to buy

友達 【とも・だち】 - friend

会う 【あ・う】 (u-verb) - to meet

買い物 【か・い・もの】 - shopping

お金 【お・かね】 - money

ある (u-verb) - to exist (inanimate)

いい (i-adj) - good

家 【1) うち; 2) いえ】 - 1) one's own home; 2) house

帰る 【かえ・る】 (u-verb) - to go home

誰 【だれ】 - who

いる (ru-verb) - to exist (animate)

アメリカ - America

たくさん - a lot (amount)

太る 【ふと・る】 (u-verb) - to become fatter

I call this next conditional the past conditional because it is produced by taking the past tense and just adding 「ら」. It is commonly called the 「たら」 conditional because all past-tense ends with 「た／だ」 and so it always becomes 「たら／だら」. Like the 「ば」 conditional, it is also a general conditional.

Conjugation Rule for 「たら（ば）」

First change the noun, adjective, or verb to its past tense and attach 「ら」
Examples

自動 → 自動だった → 自動だったら

待つ → 待った → 待ったら

読む → 読んだ → 読んだら

忙しい → 忙しかった → 忙しかったら

Examples

暇だったら、遊びに行くよ。
If I am free, I will go play.

学生だったら、学生割引で買えます。
If you're a student, you can buy with a student discount.

For i-adjectives and verbs, it is very difficult to differentiate between the two types of conditionals, and you can make life easier for yourself by considering them to be the same. However there is a small difference in that the 「たら」 conditional focuses on what happens after the condition. This is another reason why I call this the past conditional because the condition is "in the past" (not literally) and we're interested in the result not the condition. The 「ば」 conditional, on the other hand, focuses on the conditional part.

Let's compare the difference in nuance.

Example 1

Ａ：友達に会えれば、買い物に行きます。
A: We will go shopping, if I can meet with my friend.

Ｂ：友達に会えたら、買い物に行きます。
B: If I can meet with my friend, we will go shopping.

Example 2

Ａ：お金があればいいね。
A: It would be good, if I had money, huh?

Ｂ：お金があったらいいね。
B: If I had money, it would be good, huh?

Going by the context, the 「～たら」 form sounds more natural for both examples because it doesn't seem like we're really focusing on the condition itself. We're probably more interested in what's going to happen once we meet the friend or how nice it would be if we had money.

The past conditional is the only type of conditional where the result can be in the past. It may seem strange to have an "if" when the result has already taken place. Indeed, in this usage, there really is no "if", it's just a way of expressing surprise at the result of the condition. This has little to do with conditionals but it is explained here because the grammatical structure is the same.

家に帰ったら、誰もいなかった。
When I went home, there was no one there. (unexpected result)

アメリカに行ったら、たくさん太りました。
As a result of going to America, I got really fat. (unexpected result)

You can also use 「たらば」 instead of 「たら」. Similar to 「ならば」, this means exactly the same thing except that it has a more formal nuance.

How does 「もし」 fit into all of this?

Vocabulary

もし - if by any chance

いい (i-adj) - good

映画 【えい・が】 - movie

観る 【み・る】 (ru-verb) - to watch

行く 【い・く】 (u-verb) - to go

時間 【じ・かん】 - time

ある (u-verb) - to exist (inanimate)

明日 【あした】 - tomorrow

Some of you may be aware of the word 「もし」 which means "if" and may be wondering how it fits into all of this. Well, if you want to say a conditional, you need to use one of the conditionals discussed above. 「もし」 is really a supplement to add a sense of uncertainty on whether the condition is true. For instance, you might use it when you want to make an invitation and you don't want to presume like the following example.

もしよかったら、映画を観に行きますか？
If by any chance it's ok with you, go to watch movie?

もし時間がないなら、明日でもいいよ。
If given that there's no time, tomorrow is fine as well. (Not certain whether there is no time)